The area of the triangle is a=( m x n) /2 in cm² , implies 2xa = m xn the area of the rectanglle A= n x m in cm² but we know <span> 2xa = m xn = A, </span> that means the surface of the rectangle is 2 times of the area of the triangle
Because the amount is doubling every day, we can use the expression 1*2^15-1 because there is 1 to start with. Also cool trick! if you need to do 2^1+2^2+2^3+....+2^x, it will be equal to 2^(x+1)-1. So: